title: Social foragers adopt a riskier foraging mode in the centre of their groups.
abstract: Foraging in groups provides many benefits that are not necessarily experienced the same way by all individuals. I explore the possibility that foraging mode, the way individuals exploit resources, varies as a function of spatial position in the group, reflecting commonly occurring spatial differences in predation risk. I show that semipalmated sandpipers (Calidris pusilla), a social foraging avian species, tended to adopt a riskier foraging mode in the central, more protected areas of their groups. Central birds effectively used the more peripheral group members as sentinels, allowing them to exploit a wider range of resources within the same group at the same time. This finding provides a novel benefit of living in groups, which may have a broad relevance given that social foraging species often exploit a large array of resources.
authors.affiliation: Faculty of Veterinary Medicine, University of Montreal, , PO Box 5000, Saint-Hyacinthe, Québec, Canada , J2S 7C6.
authors.forename: Guy
authors.initials: G
authors.lastname: Beauchamp
mesh_terms: D000818:Animals; D001070:Appetitive Behavior; D001522:Behavior, Animal; D046091:Charadriiformes / Q000502:physiology*; D017753:Ecosystem; D005247:Feeding Behavior / Q000502:physiology*; D016018:Least-Squares Analysis; D011235:Predatory Behavior; D012306:Risk; D012919:Social Behavior; D014741:Video Recording
keywords: antipredator vigilance; semipalmated sandpipers; social foraging; spatial position